Timothy w



(No Model.)

T. W. MURPHY.

NUT AND BOLT LOCK.

No. 587,012.; -Patented July 27,1897.

UNITED. STATES PATENT OFFICE.

TIMOTHY W. MURPHY, OF \VASHINGTON, DISTRICT OF COLUMBIA.

.NUT AND BOLT LOCK.

SPECIFICATION forming partof Letters Patent No. 587,012, dated July 27,1897. Application filed December 16,1896. $erial No. 615,885 (No model.)

. To all whom it may concern:

Be it known that I, TIMOTHY WV. MURPHY, a citizen of the United States,residing at Washington, in the District of Columbia, have inventedc'ertain new and useful Improvements ,irnNut and Bolt Locks; and I dohereby deand bolt locks, and is illustrated in the accompanyingdrawings, in which- Figure 1 is a View showing a bolt in elevation andthe nut and lock or key in crosssection. Fig. 2 is a view showing thelock or key in plan and the nut and bolt in horizontal section along theplane indicated by the line 2 2 in Fig. 1. Fig. 3 is a view showing thelock 'or key in perspective and enlarged. Fig. 4.- is a view showing thenut and lock or key in perspective, the key having been inserted inthenut a portion only of its length. Fig. 5 is a plan of the key from itslower side, enlarged.

In the drawings the letter A indicates an ordinary bolt having the usualthreaded end;

B, a nut havingthe usual threaded opening adapted to receive the end ofthe bolt and provided with a dovetail groove in-its upper facetangential to and intersecting the threaded opening, and O a key or lockadapted to fit within the dovetail groove in the nut and to cut a seatin the bolt, thereby locking nut and bolt together. I

The nut B has a dovetail groove 12 in its upper face tangential to andintersecting the threaded bolt-opening. The said groove is undercut orhas a shoulder b overhanging it on its inner side. The shoulder b inmany instances is divided on either side of the point where the threadedopening and the groove meet, the bolt-openingand the groove merging intoeach other in practice, not in theory. The key or lock 0 has across-section to correspond with and to enable it to fit into the groove6 and has a step or offset 0 to engage the shoulder 19. The length of'the key 0 along its upper portion 0 is exactly the length The lowerportion of the key from the step c to its base is cut away short of theextremity of one end at an angle and forms a cutting edge 0, the upperportion 0 projecting beyond this cutting edge and protecting it. Thewhole key or merely the cutting edge 0 is tempered or rendered harderthan the material of the bolt, or it may be made of a harder anddifferent material therefrom.

My improved nut and bolt lock is used as follows: The bolt A having beenplaced in position the nut B is screwed home upon its threaded end andthe end of the key 0 having the cutting edge 0 nearest it is inserted inoneend of the groove 1), the cutting edge 0 being upon the side of thegroove next to the bolt. If the key consisted only of the upperportions, it would pass the bolt, merely grazing its threads, but thecutting edge e is set forward by the step 0- a distance slightly greaterthan the screw-threads on the bolt. A few sharpblows, however, drive thekey completely within the groove in the nut, the cutting edge 0' plowingits way through the threads and some little into the body of the bolt,thus forming a seat for itself and looking the nut and bolt together.The end of the upper portion of the key 0, projecting beyond the cuttingedge e, is a protection to said edge either when carried loosely priorto use or when it is desired to force the key from its seat to releasethe nut from the bolt.

The key may have its cutting edge on either side-'that is, on its right,as shown in the drawings, or on its left. The advantage of placing theedge on the right, however, is that the blows which drive it hometighten the nut.

Having thus fully described myinvention, what I claim as new, and desireto secure by Letters Patent of the United States, is-

1. In a nut and bolt lock the combination with a bolt having a threadedend, of a nut having a threaded opening adapted to receive said end,said nut having a dovetail groove of a key adapted to fit said groove,said key in its upper face tangential to and intersecthaving a cuttingedge short of its end. IO ing its threaded opening, and a key adapted Intestimony whereof I affix my signature to fit said groove, said keyhaving a cutting in presence of two witnesses.

edge on its lower side short of one end. TIMOTHY W. MURPHY.

2. In a nut and bolt lock the combination Vitnesses:

with a bolt and a nut, the nut having a dove- HORACE B. CLIFTON,

tail groove intersecting its threaded opening, CORCORAN THOM.

